The invention relates to a jet regulator having a sleeve-shaped jet-regulator housing, which can be mounted on the water outlet of a sanitary outlet fitting, and having a sealing ring comprised of an elastic material, which has a rectangular cross section with approximately parallel longitudinal walls and which seals in the axial direction against an adjacent annular surface on the water outlet of the outlet fitting.
FR 2 948 133 A1 discloses a jet regulator having a sleeve-shaped jet-regulator housing, which can be mounted on the water outlet of a sanitary outlet fitting. A sealing ring is provided in order to be able to seal the jet-regulator housing in the axial direction against an adjacent annular face on the water outlet of the outlet fitting. The sealing ring, which has a rectangular cross section with approximately parallel longitudinal walls, is inserted into the jet-regulator housing on the inflow side in such a manner that the sealing ring, with the part-region facing toward the jet-regulator housing, fits closely in a frictionally engaged manner on the housing inner circumference of the jet-regulator housing, whereas that part-region of the sealing ring which faces away from the jet-regulator housing protrudes beyond the jet-regulator housing. There is, however, the risk of the sealing ring being unintentionally deformed, in such a manner that the sealing ring falls out of the jet-regulator housing and is lost, during shipping or mounting of the disclosed jet regulator. Since loss of the sealing ring also causes the remaining components of the disclosed jet regulator to lose their retention in the jet-regulator housing, there is the risk of the disclosed jet regulator coming apart and being almost impossible, in particular for the unacquainted user, to reassemble in a properly functioning manner.
NL 110 837 C discloses a screw connection intended for the assembly of two pipe sections. For this purpose, these two pipe sections have, on their mutually facing pipe ends, mutually corresponding threads, such that the first pipe end featuring an external thread can be screwed into the internal thread provided in the adjacent second pipe end. In order to secure this screw connection, a lock nut is screwed onto the external thread provided on the first pipe end. This lock nut has, on its end side facing toward the second pipe end, a depression which features an encircling undercut protruding radially toward the inside. A sealing ring, which on the outer circumference has an annular shoulder, is inserted into this depression. This annular shoulder is engaged from behind by the undercut in such a manner that the sealing ring is securely retained with slight axial play on the lock nut. Since the sealing ring in the disclosed screw connection has a complex contour, its manufacture requires a relatively high outlay. Due to its complex contour, the sealing ring is unable to provide a uniform sealing effect over its entire bearing face.
A jet regulator, which is to form a homogenous, non-spraying and sparkling soft water jet at the water outlet of a sanitary outlet fitting, is disclosed in EP 1 770 225 B1. The disclosed jet regulator has a sleeve-shaped jet-regulator housing, jet-forming functional elements being provided in its housing interior. A sleeve-shaped outlet mouthpiece, into which the jet-regulator housing can be inserted from the inflow side as far as an insertion stop, is assigned to the disclosed jet regulator. The outlet mouthpiece has an internal thread which interacts with an external thread on the water outlet of the outlet fitting. The jet regulator disclosed in EP 1 770 225 B1 is secured in the outlet mouthpiece with a sealing ring comprised of an elastic material, said sealing ring being intended for sealing in the axial direction between the inlet-side end-edge region of the jet-regulator housing and an adjacent annular face on the water outlet of the outlet fitting. In order to captively retain the sealing ring in the outlet mouthpiece, at least one retaining projection, which protrudes into the internal thread on the inner circumference of the outlet mouthpiece, is provided on the outer circumference of the sealing ring. The sealing ring designed with at least one retaining projection can, however, only be utilized in an advantageous manner together with an outlet mouthpiece.
However, jet regulators which feature an external thread on the outer circumference of their sleeve-shaped jet-regulator housing have already been created. These disclosed jet regulators can, with the external thread provided on their jet-regulator housing, be screwed into an internal thread on the water outlet in such a manner that such a jet regulator terminates in an approximately flush manner with the outflow-side end edge of the water outlet. These jet regulators, which feature an external thread, do not rely on an additional outlet mouthpiece. In the case of such jet regulators, the required sealing ring can only be added with the risk that the sealing ring could potentially be lost during storage and shipping.